The present invention relates to an electron beam device (EBD), and in particular to an EBD with improved properties in relation to a cathode housing thereof.
A typical EBD comprises a vacuum tight body inside which a cathode housing is arranged. The cathode housing comprises a filament which is heated by a current in order for electrons to be produced. The thus produced electrons are accelerated by means of a high-voltage potential and exits through an exit window of the body, typically a thin window foil supported by a support grid. Electron beam devices may be used for several purposes, such as curing of paint or adhesives, or sterilisation of volumes or surfaces. Depending on the application properties such as acceleration voltage, beam profile, shape of the EBD will vary. The teachings of the present invention may advantageously be applied to EBD:s used for sterilization of a web of packaging material, since it may significantly improve the performance of EBD:s being designed for that purpose. It is to be understood, however that it may be applied to other EBD:s having a similar construction for which similar advantages may be obtained.
Within the field of sterilization of a web of packaging material, performance factors such as stability, durability and longevity are key issues, once the quality of the sterilization is ensured. All components mentioned and still more may be optimized in order for the EBD to produce the desired beam shape under any given circumstances.
The present invention relates to the context of elongate electron beam devices used for treatment of larger surface, such as webs of packaging material used for production of packaging containers. More specifically the present invention relates to improvements of such EBD:s, in terms of ensuring adequate quality while simplifying assembly of the EBD.